Index: sources/model/mtreatmentranges.h
===================================================================
diff -u -r31b9ae63410e7ca23f0f849e38368880e4c402b4 -rd3f916066c2d10c10fffa91fd8a7e5ac6dd86c7d
--- sources/model/mtreatmentranges.h	(.../mtreatmentranges.h)	(revision 31b9ae63410e7ca23f0f849e38368880e4c402b4)
+++ sources/model/mtreatmentranges.h	(.../mtreatmentranges.h)	(revision d3f916066c2d10c10fffa91fd8a7e5ac6dd86c7d)
@@ -19,9 +19,17 @@
 // Project
 #include "types.h"
 
+// forward declarations
+class tst_models;
+
+
 namespace Model {
 
 class MTreatmentRanges {
+
+    // friends
+    friend class ::tst_models;
+
 public:
     QString  stringPrefix = "Treatment Ranges";
     struct Data {
@@ -48,7 +56,7 @@
 
     QString toString        (                               ) const ;
     void    toVariantList   (      QVariantList &vData      ) const ;
-    bool    fromByteArray   (const QByteArray   &vByteArray );
+    bool    fromByteArray   (const QByteArray   &vByteArray , int *vIndex = nullptr);
 
     Data    data() const;
 };